1. Field of the Disclosure
This disclosure relates generally to work strings deployed in wellbores for the production of hydrocarbons from subsurface formations, and in particular to a joint of a work string that may be uncoupled without causing undue stress to the members of the joint.
2. Description of the Related Art
Wellbores for hydrocarbon exploration and production can extend to great well depths, often more than 15,000 ft. Various operations may be performed at these depths, including fracturing (“fracking” or “fracing”) operations, completion operations and production operations. For such operations, an assembly of a string containing at least two parts is deployed in the wellbore to a selected depth. The at least two parts are generally connected to each other and locked into a first configuration with respect to each other via shear screws while being conveyed downhole. Expansion and contraction occurs between the two connected parts in the wellbore, resulting in stress on the assembly. Once the assembly has reached its selected downhole location, shear forces are applied along the assembly, causing the shear screws to sever or break, thereby allowing the at least two parts of the assembly to move relative to each other and to alleviate stress. At deeper wellbores, longer strings are used. Thus, shear screws are required to be stronger in order to support the increased weight. However, the shear forces necessary for severing such strong shear screws may cause damage to one or more of the parts of the assembly and any other associated downhole equipment. Therefore, there is a need to unlock assemblies at a downhole location without causing damage to downhole equipment.